DURA-EUROPOS is best known to historians as the site of an ancient Syrian synagogue with marvelous frescoes of biblical episodes. But it's been in the news recently because excavators have found evidence in it of early chemical warfare:

Why Chemical Warfare Is Ancient History

By Ishaan Tharoor Friday, Feb. 13, 2009 (Time Magazine)

The prospect of chemical and biological warfare in this age of anthrax scares and WMD can feel — like the threat of nuclear Armageddon before it — like a uniquely modern terror. But a British archaeologist's recent find offers a reminder that chemical weapons are nothing new — in fact, they are nearly 2,000 years old. Simon James, a researcher at the University of Leicester in the U.K., claims to have found the first physical evidence of chemical weaponry, dating from a battle fought in A.D. 256 at an ancient Roman fortress. James concluded that 20 Roman soldiers unearthed beneath the town's ramparts did not die of war wounds, as previous archaeologists had assumed, but from poison gas.

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